In a motorcycle, it is possible to start an engine with cell starting by a cell motor starter receiving an electric power from a battery and kick starting by a kick pedal which a driver presses with a foot. At the cranking time of a fuel injection engine, an optimum amount of fuel injection and an optimum ignition time are different in the case of the cell starting and in the case of the kick starting. The engine is provided with an ECU (engine control unit), and in response to a driving state, the ECU adjusts an amount of fuel injection and an ignition time to an optimum state in accordance with a program according to a map or the like decided in advance and controls to drive the engine. At the time of commencement of engine start, a detection device (circuit) is provided in a starter switch between the battery and the cell motor, and the ECU detects whether or not the cell motor has been driven according to a signal from this detection device to judge whether the engine is started by the cell starting or the kick starting. According to the judgment, the ECU can select a program to perform driving control at the time of commencement of engine start.
However, the detection device of the starter switch may not be provided in the case in which a restriction in terms of space is large, in particular, in a small motorcycle or the like and a structure thereof is desired to be simplified, the case in which cost is desired to be reduced, or the like. In such a case, a program is set according to a map or the like matched to one of the cell starting or the kick starting, and the driving control at the time of commencement of engine start is performed using the same program in both the cell starting and the kick starting without any distinction.
Consequently, it is likely that, in the case of the cell starting or the kick starting, the engine cannot be driven with an optimum amount of fuel injection and at an optimum ignition time to decrease startability and deteriorate exhaust gas emission.
The present invention has taken into account the above-mentioned related art, and it is an object of the present invention to provide an engine start control method and an engine start control apparatus which can distinguish cell starting and kick starting with a simple constitution without using a detection device of a starter switch to perform optimum engine start according to the respective starting.